1. Field Of The Invention
The present invention deals with the field of devices usable for forming of emergency life vests which are pneumatically inflatable and are commonly used on airplanes, boats and in other environments where human life threatening situations may occur and flotation vests are desired to be made available. Heretofore most methods for forming such pneumatically inflatable life vests have included extensive sewing operations. With the apparatus and method of the present invention a one-step single heat pressing step allows for complete formation of all securement and sealing operations required for formation of the vest. This single heat sealing step simultaneously forms the flotation chambers and seals the interconnecting neck gusset in place.
2. Description Of The Prior Art
Examples of prior art structures for forming life vests and for prior art patents on such formed life vests see U.S. Pat. Nos. 2,633,443 patented Mar. 31, 1953 to N. Langer on a Method Of Heat-Sealing; 2,705,523 patented Apr. 5, 1955 to V. H. Hasselquist on a Heat-Seaming Apparatus For Thermoplastic Sheet Materials; 2,957,513 patented Oct. 25, 1960 to A. Schneider et al on a Method And Apparatus For Heat Sealing And Severing By Means Of A Stencil And Hot Gas Stream; 3,002,203 patented Oct. 3, 1961 to H. J. Moran on an Inflatable Life Preserver; 3,037,220 patented June 5, 1962 to W. L. Jantzen on a Sail-Float; 3,068,500 patented Dec. 18, 1962 to B. R. Silverman et al on a Life Vest Preserver; 3,441,964 patented May 6, 1969 to H. Koch et al on a Life Jacket; 3,462,330 patented Aug. 19, 1969 to J. W. Greig et al on a Method For Making A Hollow Plastic Core Structure; 3,988,795 patented Nov. 2, 1976 to Robertson on a Life Preserver; 4,035,857 patented July 19, 1977 to Briley et al on a Divers Buoyancy Vest; 4,083,742 patented Apr. 11, 1978 to T. Sugimoto on a Process For Producing Ornamental Standing Toys; 4,193,153 patented Mar. 18, 1980 to Tyrer et al on a Life Jacket; 4,302,270 patented Nov. 24, 1981 to R. D. Nicolet on a Method Of Bonding An Ultrafiltration Membrane Assembly; 4,561,853 patented Dec. 31, 1985 to Faulconer et al on a Buoyancy Compensator, Bladder, And Process Of Manufacture and 4,654,016 patented Mar. 31, 1987 to Pendleton on a Buoyant Vest And Method Of Making The Same.